Authors:

Yun Liu(University of Delaware/National Institute of Standards and Technology)

Peter Falus(Institut Laue-Langevin)

Lionel Porcar(Institut Laue-Langevin)

Emiliano Fratini(University of Florence)

Wei-Ren Chen(Oak Ridge National Laboratory)

Antonio Faraone(University of Maryland/National Institute of Standards and Technology)

Kunlun Hong(Oak Ridge National Laboratory)

Piero Baglioni(University of Florence)

Intermediate range order (IRO) has been recently observed in lysozyme
solution that is caused by a combination of a short-range attraction and
long-range repulsion. At very high concentration, there is observed cluster
formation in lysozyme solutions that is one type of IRO structures. Here, we
investigate the temperature effect on the dynamic cluster formation and
identify the transition concentration from a monomeric protein phase to a
cluster phase. The normalized short-time self-diffusion coefficient is not
affected by changing attraction strength at the concentration of about
10{\%} mass fraction, indicating that the system is still dominated by
monomeric protein phase. However, at high concentrations, the average
self-diffusion coefficient is sensitive to the change of short-range
attraction strength, which is interpreted due to the growth of the size of
dynamic clusters in solution. The transition concentration from dominating
monomeric phase to dynamic cluster phase is estimated to be around 14 {\%}
mass fraction.

To cite this abstract, use the following reference: http://meetings.aps.org/link/BAPS.2013.MAR.J34.3